Steen Township is one of ten townships in Knox County, Indiana. As of the 2020 census, its population was 803 (down from 900 at 2010) and it contained 361 housing units.
Steen Township was founded in 1857. It was named for Richard Steen, a pioneer settler.
Andrew Nicholson Farmstead was added to the National Register of Historic Places in 2005.
According to the 2010 census, the township has a total area of , of which (or 98.89%) is land and (or 1.14%) is water.